Administration of Vitamin D Metabolites Affects RNA Expression of Xenobiotic Metabolising Enzymes and Function of ABC Transporters in Rats

From studies on different species and in cell culture systems, it has been suggested that vitamin D metabolites might affect themetabolism and elimination of xenobiotics. Although most studies performed on rodents and cell cultures report an upregulationof respective enzymes and transporters, data from the literature are inconsistent. Especially results obtained with sheep differ fromthese observations. As vitamin D metabolites are widely used as feed additives or therapeutics in livestock animals, we aimed toassess whether these differences indicate species-specific responses or occurred due to the very high dosages used in the rodentstudies. -erefore, we applied treatment protocols to rats that had been used previously in sheep or cattle. Forty-eight female ratswere divided into three treatment and corresponding placebo groups: (1) a single intraperitoneal injection of 1,25-(OH)2D3 orplacebo 12 h before sacrifice; (2) daily supplementation with 25-OHD3 by oral gavage or placebo for 10 days; and (3) a singleintramuscular injection of vitamin D3 10 days before sacrifice. In contrast to a previous study using sheep, treatment of rats with1,25-dihydroxyvitamin D3 did not result in an upregulation of cytochrome P450 3A isoenzymes (CYP3A), but a decrease wasfound in hepatic and intestinal expressions. In addition, a downregulation of P-glycoprotein (P-gp) and breast cancer resistanceprotein was found in the brain. Taken together, the stimulating effects of vitamin D metabolites on the expression of genesinvolved in the metabolism and elimination of xenobiotics reported previously for rodents and sheep could not be reproduced. Incontrast, we even observed a negative impact on the expression of CYP3A enzymes and their most important regulator, thepregnane X receptor. Most interestingly, we could demonstrate an effect of treatment with 25-hydroxyvitamin D3 and vitamin D3on the functional activity of ileal P-glycoprotein (P-gp) using the Ussing chamber technique.Fil: Klumpp, Karoline. University of Veterinary Medicine Hannover. Institute of Physiology and Cell Biology; AlemaniaFil: Lange, Frauke. University of Veterinary Medicine Hannover. Institute of Physiology and Cell Biology; AlemaniaFil: Muscher-Banse, Alexandra S.. University of Veterinary Medicine Hannover. Institute of Physiology and Cell Biology; AlemaniaFil: Schnepel, Nadine. University of Veterinary Medicine Hannover. Institute of Physiology and Cell Biology; AlemaniaFil: Hansen, Kathrin. University of Veterinary Medicine Hannover. Institute of Physiology and Cell Biology; AlemaniaFil: Lifschitz, Adrian Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Maté, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Wilkens, Mirja. University of Veterinary Medicine Hannover. Institute of Physiology and Cell Biology; Alemani

Dean Bergman

Dr. H. D. Bergman, for twenty-seven years head of the Department of Veterinary Physiology and Pharmacology at Iowa State, has been named dean of the Division of Veterinary Medicine and director of the Veterinary Research Institute, succeeding Dr. Charles Murray. The new dean has devoted his entire professional career to veterinary education and state and national veterinary organization work

Służba medycyny weterynaryjnej w Bydgoszczy. Historia i teraźniejszość

The operations of the veterinary medicine service in Bydgoszcz in the scientific and research scope are connected with the functioning of the National Veterinary Research Institute in Puławy Branch in Bydgoszcz (PlWetPIB). The institution, with traditions dating back to the Prussian Department of the Animal Hygiene Institute attached to the Emperor William Royal Agricultural Institute, was developing innovative research in veterinary medicine from the very beginning. Professor Kazimierz Panek stood out particularly; in the inter-war period he conducted innovative research in the scope of physiology and bacteriology. After World War Two, eminent scientists were employees of this institution, e.g. professor E. Domański, professor L. Jaśkowski, and professor E. Wiśniowski, who managed the Animal Hygiene Department in the years 1960-1985. The operations of veterinarians employed by the Municipal Slaughterhouse, and then the Meat Works, were also important. The post-war history of the veterinary medicine service in Bydgoszcz is connected with the operations of the State Veterinary Clinic, whereas the functioning of the Voivodeship Veterinary Inspectorate (WIW) focuses on contemporary issues of the activity of the veterinary medical service in Bydgoszcz

Veterinary Medicine in Norway

The following is a report on observations made during the academic year 1960-61 while the author was engaged in study and research at the Institute of Reproductive Physiology and Pathology of the Veterinary College of Norway, Oslo. This activity was supported by a North Atlantic Treaty Organization Postdoctoral Fellowship under the direction of the National Science Foundation. A number of such fellowships are awarded each year in all areas of science to foster the understanding and exchange of information between scientists of the North Atlantic Treaty countries and to encourage the scientific careers of young men in the various fields of science

Occasional Publications on Northern Life, No. 04

The need to exchange information on research in reindeer and caribou diseases became apparent to investigators attending the Second International Reindeer/Caribou Symposium in Roros, Norway, in 1979. Initially, bibliographies were to be exchanged by being submitted to and subsequently distributed by workers at the University of Alaska. When the bibliographies were submitted, it seemed sensible to computerize the lists to facilitate searches for specific information in the future. An apparently simple task became amazingly complex. This is the resultant collection of publications by reindeer/caribou disease researchers. Because researchers in wildlife diseases tend to work on more than one species or topic, out of interest or necessity, a decision was made to include all of a person's references rather than to limit them to strictly reindeer/caribou diseases. The authors hope this will provide a good basis for exchange of information among all those interested in reindeer/caribou diseases

Vitamin D and calcium metabolism in horses in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Science at Institute of Veterinary, Animal and Biomedical Sciences (IVABS), Massey University, Manawatū, New Zealand

The physiology of vitamin D in horses has not been studied in great depth. Few studies on vitamin D metabolites (25OHD2, 25OHD3, and 1,25(OH)2D) and their relationship to other serum analytes exist. In addition, some studies suggest that equine vitamin D physiology may be different from other species. This thesis aimed to investigate aspects of vitamin D metabolism in horses. The effect of blanketing on vitamin D synthesis and its relationship with other analytes involved in calcium homeostasis, including vitamin D metabolites (25-hydroxyvitamin D2 (25OHD2), and 25-hydroxyvitamin D3 (25OHD3), 1,25-dihydroxyvitamin D (1,25(OH)2D)), ionised calcium (iCa), total calcium (tCa), phosphorus (P), total magnesium (tMg) and parathyroid hormone (PTH) were studied in horses. Regardless of blanketing, 25OHD3 was undetectable in equine serum and 25OHD2 was the main form of 25OHD in circulation. A strong seasonal variation in serum 25OHD2, 1,25(OH)2D, iCa, tCa, P, tMg and PTH concentrations was detected, although no differences were seen between horses that were blanketed and those that were not. The circadian rhythms of serum vitamin D metabolites, iCa, tCa, P, tMg, and PTH concentrations in horses was studied over 48 h on the summer and winter solstices. A significant difference was seen between the serum concentrations of studied analytes between solstices, with no rhythm detected in winter. An in vivo study suggested that equine skin may be unable to convert 7-dehydrocholesterol (7-DHC) to vitamin D3 after exposure to ultraviolet B (UVB) light. Quantitative PCR was performed on equine kidney to study the expression of vitamin D responsive and calcium transporting genes, which were then compared to genes in sheep and dogs. The results suggested that TRPV6, calD9k /calD28k, and PMCA were the main calcium transporting pathways in the kidney of these species, and there was a high correlation between VDR and other studied genes. It was concluded that 25OHD2 is the main metabolic precursor for 1,25(OH)2D and should be considered the best available index of vitamin D status in unsupplemented horses, and that horses most likely rely on diet as their primary source of vitamin D

A forage-only diet alters the metabolic response of horses in training

Most athletic horses are fed a high-starch diet despite the risk of health problems. Replacing starch concentrate with high-energy forage would alleviate these health problems, but could result in a shift in major substrates for muscle energy supply from glucose to short-chain fatty acids (SCFA) due to more hindgut fermentation of fibre. Dietary fat inclusion has previously been shown to promote aerobic energy supply during exercise, but the contribution of SCFA to exercise metabolism has received little attention. This study compared metabolic response with exercise and lactate threshold (VLa4) in horses fed a forage-only diet (F) and a more traditional high-starch, low-energy forage diet (forage–concentrate diet - FC). The hypothesis was that diet F would increase plasma acetate concentration and increase VLa4 compared with diet FC. Six Standardbred geldings in race training were used in a 29-day change-over experiment. Plasma acetate, non-esterified fatty acids (NEFA), lactate, glucose and insulin concentrations and venous pH were measured in samples collected before, during and after a treadmill exercise test (ET, day 25) and muscle glycogen concentrations before and after ET. Plasma acetate concentration was higher before and after exercise in horses on diet F compared with diet FC, and there was a tendency ( P50.09) for increased VLa4 on diet F. Venous pH and plasma glucose concentrations during exercise were higher in horses on diet F than diet FC, as was plasma NEFA on the day after ET. Plasma insulin and muscle glycogen concentrations were lower for diet F, but glycogen utilisation was similar for the two diets. The results show that a high-energy, forage-only diet alters the metabolic response to exercise and, with the exception of lowered glycogen stores, appears to have positive rather than negative effects on performance traits

Mapping the teaching of aquatic animal veterinary medicine in the European Union and European Free Trade Area

Aquatic animal production is the fastest growing food sector globally. Aquaculture and fisheries are very dynamic sectors in the EU and the number of ornamental aquarium pets is increasing. Veterinarians have a fundamental role to play by ensuring health and welfare of aquatic species, productivity and profitability of fish farming, public health and ecosystem conservation. This study investigates how the undergraduate curriculum prepares future veterinarians for such roles by analysing data from the 77 European veterinary education establishments based in EU and the European Free Trade Area. Over 95 per cent of these establishments incorporate teaching in aquatic animal veterinary medicine in their curriculum, while the great majority do so within the core curriculum. Almost half of the establishments provide teaching in aquatic animal veterinary medicine as separate subjects. Many establishments (>40 per cent) provide such training as elective option in their undergraduate curricula or as postgraduate opportunities to enhance Day One Competences. The veterinary education establishments integrating adequately aquatic animal veterinary medicine in their curriculum are evenly distributed in all regions of Europe. Veterinarians are trained and empowered by legislation to assess health of aquatic animals, to diagnose, to prescribe medicines, to notify for diseases and to ensure safe food for the consumers. Veterinary education establishments should encourage training of veterinarians to follow a career in aquatic animal veterinary medicine